package thread;

import java.util.ArrayList;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

class TaskWithResult implements Callable<String>{
    private int id;
    public TaskWithResult(int id){
        this.id = id;
    }

    @Override
    public String call() throws Exception {
        return "result of TaskWithResult "+id;
    }
}
public class CallableDemo {
    public static void main(String[] args) {
        ExecutorService exec = Executors.newCachedThreadPool();
        ArrayList<Future<String>> results = new ArrayList<Future<String>>();
        for (int i = 0;i < 10;i ++){
            results.add(exec.submit(new TaskWithResult(i)));
        }
        for (Future<String> fs : results ){
            try{
                System.out.println(fs.get());
            }
            catch (Exception ex){
                System.out.println(ex);
                return;
            }
            finally {
                exec.shutdown();
            }
        }
    }
}
